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arXiv · 2307.02528

Phenomenology of bond and flux orders in kagome metals

Glenn Wagner·Chunyu Guo·Philip J. W. Moll·Titus Neupert·Mark H. Fischer
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Abstract

Despite much experimental and theoretical work, the nature of the charge order in the kagome metals belonging to the family of materials AV$_3$Sb$_5$ (A=Cs,Rb,K) remains controversial. A crucial ingredient for the identification of the ordering in these materials is their response to external perturbations, such as strain or magnetic fields. To this end, we provide a comprehensive symmetry classification of the possible charge orders in kagome materials with a $2\times2$ increase of the unit cell. Motivated by the experimental reports of time-reversal-symmetry breaking and rotational anisotropy, we consider the interdependence of flux and bond orders. Deriving the relevant Landau free energy for possible orders, we study the effect of symmetry-breaking perturbations such as strain and magnetic fields. Our results, thus, provide a roadmap for future tests of these intricate orders.

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Glenn Wagner, Chunyu Guo, Philip J. W. Moll, Titus Neupert, Mark H. Fischer. 2023-07-05. Phenomenology of bond and flux orders in kagome metals. https://doi.org/10.1103/physrevb.108.125136

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